Is Your Exhaust Fan Rated for the Size of Your Bathroom?

This might seem like a small part of your bathroom but exhaust fans can make a big difference. Exhaust fans help remove moisture from a room. Which, we all know bathrooms create plenty of. Fans also help eliminate and control bathroom odors. Not just the ones you are thinking of though. This includes reducing fumes from cleaning agents too. Essentially, they help with indoor air quality. However, not all exhaust fans are created equal. That is why we want to make sure you have the right exhaust fan for your bathroom.

Rated for Size & Sones

For bathroom fans to provide proper ventilation, you have to consider air movement. Air movement is measured in CFM or cubic feet per minute. This is a standard measurement and without getting too technical, you basically need one CFM per square foot in a bathroom. For example, an average bathroom size of 5′ x 8′ would require a 40 CFM fan. However, the minimum requirement is 50 CFM, so a basic exhaust fan works on most bathrooms.

You can keep it simple or go all out. Just make sure they are the right size for your bathroom.

It’s when you have large bathrooms, typically in a master suite, that you need to consider more than a basic fan. You should also add 50 CFM for each toilet, shower, and/or tub. 100 CFM if you have a jetted tub. The bigger the bathroom, the more CFM rating it will require. To determine the minimum CFM rating, use this formula:

Length x Width x Height x 0.13 = Minimum CFM rating

Keep in mind that the majority of fans are rated between 50 and 110 CFM. If you do have a larger bathroom, this, and the added fixtures are important to consider. There are also other factors you should know too. Sound levels are important as well.

For bathroom fans, the sound levels are rated in sones. The lower the sone rating, the quieter the fan. For reference, here is a video on the sound comparison. It is best to start with the sizing and then consider the sone rating. Although, make sure you don’t sacrifice the fan’s air quality capacity before the noise level. If you have to sacrifice one, make sure your size goes before the sones.

Exhaust Fan Features

Aside from the size and sones, there are additional features an exhaust fan can come with. Technology has come a long way, and so has your bathroom fan. You can get them with lights, there are also products that allow you to recess the fan and light. There are ones with humidity and moisture sensors. And even those with heat lamps. If you have ever left a fan on all day, there are options for timed fans as well. All these different features help with humidity levels, overall design, and energy efficiency.

It may seem like a small feature, but it can make a big impact. So, while it might seem like an afterthought in comparison to picking out sinks or tile colors, it is necessary to make sure you have the right one. This is just one of the many factors we take into consideration at our Kitchen & Bath Design Center. If you have questions about anything from exhaust fans to layout, we can help. Contact us today to learn more. Also, visit our blog and our Facebook page for more bathroom and home design tips.


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